Scientists searching for an HIV vaccine have been disappointed yet again. Johnson & Johnson says it has shut down a vaccine trial in Africa that started in 2017 after finding that it only provided 25% protection, the New York Times reports. The trial involved young women at high risk of HIV infection in five countries. Researchers say that over two years, 51 of 1,079 study participants who received the vaccine became infected with HIV, compared to 63 of 1,109 women who received a placebo. An earlier study in Thailand had suggested that the technology would be effective, but lead investigator Dr. Glenda Gray, who has been working to develop an HIV for more than 15 years, says it wasn't potent enough to deal with higher rates of HIV incidence and the low protection rate risked giving women a "false sense of security."
The Johnson & Johnson candidate is the latest in a long line of failed efforts to find an effective HIV vaccine. "HIV is a unique and complex virus that has long posed unprecedented challenges for vaccine development because of its ability to attack, hijack and evade the human immune system,” J&J Chief Scientific Officer Dr. Paul Stoffels said in a statement, per the AP. Researchers plan to continue a separate trial using a different iteration of the vaccine, which is being tested on men and transgender people in countries including the US. Moderna, which created a coronavirus vaccine using mRNA technology, said this month that it plans to test an HIV vaccine based on the same platform, reports the Times. (Read more HIV stories.)